Electrical radiator



R. BONNAVAL.

ELECTRICAL RADIATOR.

APPLICATION FILED AUG.30, 1919.

FIELZ.

WITNESSES Patented Mar. 30, 1920.

of the preferred 'ternating current flows ROBERT BONNAVAL, or PITTSBURGH, rinnwsrLvAur" A.,-v

ELECTRICAL RADIATOR.

To all whom it may concern:

Be it known that I, ROBERT BONNAVAL, a

citizen of the French Republic, at present time a resident of Pittsburgh, in the county of Allegheny and State of Pennsylvania, have invented a' new and useful Improvement in Electrical Radiators, of which the following is a specification.

This invention relates to electric heating apparatus and its object is to generate the heat and simultaneously rapidly diffuse and radiate the same. The invention comprises a fan wheel associated with the secondary of an inductor'um in a manner to diffuse or dissipate the heat as rapidly as it is generated by thesecondary of the inductorium'.

In the accompanying drawing Figure 1 is a diagram illustrating the principle of generatingthe heat; Fig. 2 is a side elevation of an apparatus for generating and diffusing the heat and showing associated control circuits diagrammatically; Fig. 3 is a face view form of the fan wheel; Fig. 4 is a cross section through the core of the transformer; Fig. 5 is a sectional view showing the manner of connecting the core to the base; and Fig. 6 is a detailed sectional view of a fan mounting showing a modification.

The principle according to which the heat is generated is illustrated in Fig. 1, in which the reference numeral 1 indicates the iron core, preferably laminated, of a transformer, which, as illustrated, forms a complete closed magnetic circuit. Surrounding one side of this core is the primary winding 2 of an inductorium, and around another side of the core is a ring or annulus 3, forming the secondary of an inductorium. Now, it is perfectly obvious that when an althroughthe primary winding 2 it induces a current in the rin or annulus 3, and that the current induced in the ring or annulus 3 is the product of the primary current (1,) multiplied by the ratio of the number of turns of the primary coil 2 to the single turn of the ring or annulus 3, which secondary current (1,) can theoretically be made as large as is necessary by providing the necessary number of turns in the primary coil, with respect to its inductance and to the reluctance of the magnetic circuit for the maximum flux density of the laminated iron core. The amount of heat evolved by the secondary s proportional to the square of this sec- Specification of Letters Patent.

current multiplied by Patented Mar. 30, 1920.

' Application filed August 30, 1919. Serial No, 320,926.

ondary current, multiplied by the ohmic resistance of the ring or annulus, to wit,

torium fan heater in which the heat is dis-- sipated as rapidly as generated, thus heatmg a maxlmum quantity of air with the expenditure of a given amount of electric current. The apparatus illustrated by Figs. 2t? 6 is constructed according to this princ1p e.

As illustrated in Figs. 2 to 5, the fan heater comprises a base 4 whicli supports a suitable transformer core, preferably laminated, comprising the portions 5, 6, 7 8 and 9, and which in turn supports an electric motor 10. The transformer core is suitably insulated from both the base 4 and the electric motor 10, such as by means of a fiber or similar connecting member 11, which may be arranged as shown in Fig. 5. Surrounding the portion 5 of the core is the primary coil 2 of the transformer. Rotat'ably mounted upon the portion 7 of the transformer 4 is a fan wheel 12, having a hub 13 of fiber or other insulating material, to in sulate it from the core and which is so constructed or formed as to provide .a complete annulus (or a plurality of aunuli) which forms the secondary of the transformer. This result may be secured by welding' or otherwise suitably securing a closed ring or annulus (one or more) to the blades of an ordinary fan wheel, or by forming the fan wheel as a disk, perforated centrally, andpressed or otherwise shaped to form blades 14, as shown. in Fig. 3. Such a fan wheel obviously provides a closed annulus so that when alternating current flows through the primary winding 2, there will be induced in the fan wheel a secondary current which is the product of the primary the ratio of the number of turns ofthe primary coil 2 to the single turn of the secondary coil (the fan). The closed ring or annulus must be as close as possible to the core to avoid highreactances. The ohmic resistance of the fan annulus is, of course, low, but since the current induced in it can be made of any value, theoretically, the amount of heat generated can be made high, and this heat, when the fan is revolved, will of course be dissipated. The amount of heat dies by the fan, per unit of time is a funct the speed of its rotation. 5 The fan wheel can be rotated in any suitable way from the motor 10, Fig. 2, showing intermeshing gears and 16 on the motor armature shaft 17 and fan hub, respectively; Fig. 6 .shows a modification in which the 0 motor is directly connected to the fan, such as by providing the fan hub With-extensions 18 which are mounted in bearings l7 formed in the core portions 6 and 8, respectively, and one of which extensions is suitably connected to the motor armature shaft 17. With this modifica ion the core no longer forms a closed magnetic circuit (which. will give the greatest output) but since the air gaps at the bearings 17 are 0 small, the output is only slightly decreased. In fact, the core need-not be a closed mag-' netic circuit. F or instance, the portions 8 and 9 of the core might be omitted, or the portions 5 and 6 might be omitted. In the 5 latter case, the primary coil would be placed around either the portion 8 or 9. Likewise, all portions of the core except 7 might be omitted and in that case the primary coil would be around this portion 7 and the fan mounted around the primary coil, or the primary coil mounted around the fan. But since there would be an easy leakage for the lines of magnetic force if the core were not substantially a closed magnetic circuit, it is 5 desirable to have as nearly a closed magnetic circuit as possible. s V y In order to prevent magnetic leakage of the transformer itself and to maintain its output, there may be placed around the core 0 a" copper shield 19, which, however, should not form a complete tube around the core, but left open, as shown in Fig. 4. A. plurality of transformers may, obviously be. used. Likewise'the secondary may be stationary, 5 theheat being removed by an ordinary ventilating fan running close to it.

. The apparatus described may be controlled byan ordinary speed regulator inthe motor circuit, but to maintain the temperature of 0 the fan constant it is also necessary to control the current through the transformer. An arrangement for regulating both the speed of the motor and controlling the temperature of the fan is shown in Fig. 2, 1n

' which 20 and 21 indicate any suitable altercuits 23 and 25, respectively, so that thereby both the transformer and motor circuits are controlled. In the transformer circuit, at

any suitable place, will be provided a suit-. 'able cut-out 29, so that, if desired, the current to the transformer may be suppressed and the fan used as an ordinary ventilator.

Obviously various arrangements of control circuits will suggest themselves to those skilled in the art. Neither do I limit, myself to the specific construction and arrangement of apparatus shown, as the same may be readily varied without departing from the spirit of my invention.

I claim:

1. An inductive electric fan heater, the fan wheel of which is constructed toform the secondary of the 'inductorium.

2. Anelectric heater comprising the pri mary winding of-an-inductorium, and a fan wheel associated therewith and constructed to formthe secondary of the inductorium.

3. An electric heater comprising the primary winding of an inductorium, and a fan wheel associated therewith and including a closed annulus forming the secondary of the inductorium. .1. M

l. An electric heater comprisingarotary fan including an annulus, a primary transformer coil, and a core common to said coil and fan annulus, whereby said annulus forms the secondary of a transformer.

5. An electric heater comprising an inductorium, a fan wheel associated therewith and constructed to form the secondary .of the inductorium, an. electric motor for rotating said fan,and circuits and mechanism ar-' ranged to control the amounts of current to the fan-motor and to the inductorium.

In testimony whereof, I have hereunto set my hand.

ROBERT BONNAVAIJ.

Witness Howarn I. SNIVELY. 

